But do you always buy cheap tho?

Or you buy a project that is going to die.
Panic sellers are good for people who do the opposite, in this case is investing. But for long term, it will make the whole market bad and not having a good momentum to go up.
These panic sellers are also good for the newbies. The beginners can get almost all cryptocurrencies for the low prices, and this is the best opportunity for them.